Israelis fear breach of Syria's chemical arsenal

Israeli Aviv Levy tries on a gas mask at a distribution center in a shopping mall in Mevaseret Zion near Jerusalem, Wednesday, July 25, 2012. Israel’s foreign minister warned on Wednesday his country will act immediately if it discovers Islamic militants are raiding Syria's chemical or biological weapons stocks, while Israelis rushed to stock up on gas masks as the bellicose rhetoric swells. (AP Photo/Sebastian Scheiner)
— AP

Israeli Aviv Levy tries on a gas mask at a distribution center in a shopping mall in Mevaseret Zion near Jerusalem, Wednesday, July 25, 2012. Israel’s foreign minister warned on Wednesday his country will act immediately if it discovers Islamic militants are raiding Syria's chemical or biological weapons stocks, while Israelis rushed to stock up on gas masks as the bellicose rhetoric swells. (AP Photo/Sebastian Scheiner)
/ AP

Israeli Aviv Levy tries on a gas mask as others wait in line, at a distribution center in a shopping mall in Mevaseret Zion near Jerusalem, Wednesday, July 25, 2012. Israel’s foreign minister warned on Wednesday his country will act immediately if it discovers Islamic militants are raiding Syria's chemical or biological weapons stocks, while Israelis rushed to stock up on gas masks as the bellicose rhetoric swells. (AP Photo/Sebastian Scheiner)— AP

Israeli Aviv Levy tries on a gas mask as others wait in line, at a distribution center in a shopping mall in Mevaseret Zion near Jerusalem, Wednesday, July 25, 2012. Israel’s foreign minister warned on Wednesday his country will act immediately if it discovers Islamic militants are raiding Syria's chemical or biological weapons stocks, while Israelis rushed to stock up on gas masks as the bellicose rhetoric swells. (AP Photo/Sebastian Scheiner)
/ AP

Israeli Hagit Ohana tries on a gas mask at a distribution center in a shopping mall in Mevaseret Zion near Jerusalem, Wednesday, July 25, 2012. Israel’s foreign minister warned on Wednesday his country will act immediately if it discovers Islamic militants are raiding Syria's chemical or biological weapons stocks, while Israelis rushed to stock up on gas masks as the bellicose rhetoric swells. (AP Photo/Sebastian Scheiner)— AP

Israeli Hagit Ohana tries on a gas mask at a distribution center in a shopping mall in Mevaseret Zion near Jerusalem, Wednesday, July 25, 2012. Israel’s foreign minister warned on Wednesday his country will act immediately if it discovers Islamic militants are raiding Syria's chemical or biological weapons stocks, while Israelis rushed to stock up on gas masks as the bellicose rhetoric swells. (AP Photo/Sebastian Scheiner)
/ AP

JERUSALEM 
Israelis rushed to get government-issue gas masks Wednesday, the latest sign of mounting fears that Syria's chemical weapons stockpiles could be used against them as the crisis there deepens.

Until a few days ago, the possibility of getting dragged into Syria's civil war was not a major issue in Israel, whose leaders have had a laser-like focus on the potential threat posed by Iran's suspect nuclear program. That changed when Syrian President Bashar Assad's grip on his country turned more doubtful last week, following startling military gains by rebels and a bomb attack that killed four top officials.

Syria on Monday threatened to unleash chemical and biological weapons if the country faces a foreign attack; Syria is believed to have nerve agents as well as mustard gas.

Israeli officials are more worried about the possibility that the weapons could fall into the hands of Islamic militants from Lebanon's Hezbollah or other groups should the regime fall.

"For us, that's a casus belli, or red line," Israeli Foreign Minister Avigdor Lieberman said Wednesday. He told Israel Radio that the government would act immediately to prevent that from happening as tensions rise along Israel's northern border.

The fighting also has hit too close for comfort with the thud of exploding mortar shells on Syrian territory near the Israeli-annexed Golan Heights, captured from Syria in 1967. That has drawn Israelis with binoculars to a strategic plateau, seeking a glimpse of the battle and expressing concern for their nearby homes.

Syria and Israel fought two wars, in 1967 and 1973, and have failed to reach a peace deal because of disagreements over the fate of the Golan Heights. However, Assad and his late father Hafez kept Syria's frontier with Israel quiet.

The Golan holds tremendous strategic importance for Israel, both as a territorial buffer that protects northern Israel, including the Sea of Galilee, and as a key water source.

Some Israeli officials fear that a power vacuum in Damascus could turn the Golan into a haven for militant groups, much as Egypt's lawless Sinai Peninsula has attracted a variety of anti-Israel radicals since the fall of longtime Egyptian leader Hosni Mubarak.

Israeli Defense Minister Ehud Barak disclosed over the weekend that he had asked the military to prepare for a possible attack on targets in Syria to secure strategic weapons in the event the Assad regime collapses. Prime Minister Benjamin Netanyahu followed suit with a similar threat.

Israel has a history of high-stakes military attacks on foreign soil.

In 1981, Israeli warplanes destroyed a nuclear reactor being built in Saddam Hussein's Iraq. In 2007, Israeli warplanes destroyed a site in Syria that the U.N. nuclear watchdog deemed to be a secretly built nuclear reactor.

Amid the flurry of threats and warnings this week, Israel's army chief, Lt. Gen. Benny Gantz, had a word of caution, telling a parliamentary committee that attacking Syrian weapons arsenals could have unforeseen consequences and drag Israel "into a broader offensive than planned."

There is concern that Hezbollah might launch a counterstrike if Israel were to attack a convoy transporting weapons from Syria to Hezbollah's base in neighboring Lebanon, an Israeli security official said.